Guava is an open source, Java based library developed by Google. It facilitates best coding practices and helps reduce coding errors. It provides utility methods for collections, caching, primitives support, concurrency, common annotations, string processing, I/O, and validations. This tutorial adopts a simple and intuitive way to describe the basic-to-advanced concepts of Guava and how to use its APIs. This tutorial will be useful for most Java developers, starting form beginners to experts. After completing this tutorial, we are confident you will find it easy to use Guava in your programs.